Polluting fume abatement apparatus

ABSTRACT

Fume abatement apparatus comprises, in combination, A. AN EXHAUST DUCT FOR PASSING A STREAM OF ENGINE PRODUCTS OF COMBUSTION HAVING ELECTRICALLY CHARGEABLE CONTENT, AND B. MEANS INCLUDING AN ION GENERATOR TO EFFECT A FLOW OF IONS INTO SAID STREAM, WITH ION DENSITY AND POLARITY TO SO CHANGE THE ELECTRICAL CHARGE OF SAID CONTENT AS TO ENHANCE SUBSEQUENT PRECIPITATION THEREOF ON A SURFACE.

United States Patent i191 Smith et a1.

[ 1 Oct. 30, 1973 POLLUTING FUME ABATEMENT APPARATUS Inventors: HaroldW. Smith, San Marino;

Donald G. Saurenman, Whittier, both of Calif.

Consan Pacific Incorporated, Whittier, Calif.

Filed: May 13, 1971 Appl. No.: 143,143

[73] Assignee:

U.S. Cl 60/275, 55/107, 55/131, 55/138, 55/146, 55/152, 55/D1G. 30,60/297 Int. Cl F0ln-3/00 Field of Search 60/275, 297; 55/2, 55/146, 152,155, 131, 138,120, DIG. 30,

r 102, 107, 140;317/2 E,2F, 3,4

References Cited UNITED STATES PATENTS Barr 60/320 3,331,192 7/1967Peterson 55/107 Primary Examiner-Douglas Hart Attorney-White, Haefligerand Hachand [57] ABSTRACT Fume abatement apparatus comprises, incombination,

a. an exhaust duct for passing a stream of engine products of combustionhaving electrically chargeable content, and

b. means including an ion generator to effect a flow of ions into saidstream, with ion density and polarity to so change the electrical chargeof said content as to enhance subsequent precipitation thereof on asurface.

8 Claims, 3 Drawing Figures VO LTA 6 E SOURCE POLLUTING FUME ABATEMENTAPPARATUS BACKGROUND OF THE INVENTION trostatics. Particularly,apparatus and methods involving modes of operation characterized by thepresent invention have not beenforthcoming. In this regard,.recent testsshow that automobiles with attached conventional devices for controllingsmog can produce around 200 billion submicron particles per cubic footof exhaust, compared with about 100 billionsuch particles for old carswithout such devices.

SUMMARY OF THE INVENTION It is a major object of the invention toprovide internal combustion engine exhaust fume abatement apparatuscomprising an exhaust duct for passing a stream of engine products ofcombustion having electrically chargeable content; and, means includingan ion generator operating to effect a flow of ions into the stream,with ion density and polarity to so change the electrical charge of suchcontent as to enhance subsequent precipitation on a surface. As will beseen, the generator may typically comprise multiple pointed tipsproximate the duct, and a high voltage supply connected with the tips.

In one form of the invention, the tips may be exposed to the exhauststream, and in another form an insulative shroud may protect the tipsfrom direct exposure to the growing exhaust, the shroud defining anoutlet for ions to pass from the tips to the stream path. As to thelatter, means may be provided to pass auxiliary gas such as air to thetips to travel with the ions into the stream. Further, the ductdownstream of the locus of ion flow into the stream may advantageouslyhave an insulative inner surface exposed to the stream; the duct maycomprise an exhaust pipe or stack extending horizontally or vertically;and the duct may direct the ion treated exhaust at the ground forcharged particle collection.

These and other objects and advantages of the invention, as well asdetails of an illustrative embodiment, will be more fully understoodfrom the following description and drawings, in which:

DRAWING DESCRIPTION FIGS. 1-3 are vertical sections showing differentforms of the invention.

DETAILED DESCRIPTION In FIG. 1, an internal combustion engine, of Otto,Diesel, Wankel or other type, is indicated schematically at asdelivering exhaust at 11 to the horizontal tail pipe or duct 12. Suchproducts of combustion may have electrically chargeable content such assubmicron particles and larger hydrocarbon molecules, and tests indicatethat there are in excess of 100 billion submicron particles per cubicfoot of exhaust.

In accordance with the invention, an ion generator is provided to effecta flow of ions into the exhaust stream 14 in the pipe, with ion densityand polarity to so change the electrical charge of the content as toenhance substantially the subsequent precipitation of the latter on asurface. In this regard, the extent of duct 80 downstream of the iongenerator may have an electrically insulative inner surface or coating(ceramic, plastic or other) at 15 exposed to the charged stream,preventing neutralization of the ions and particulate charge duringdischarge flow of the exhaust from the generator to the duct outlet 16.The latter may be directed downwardly to discharge the content 14 towardand at the ground surface 17, where the particles becomeneutralized andcollect, removed from the atmosphere.

The ion generator in FIG. 1 includes multiple pointed tips 18 proximateto, as for example, within the duct 12, and ahigh voltage supply 19electrically connected with the tips. The latter may be defined bymetallic needle 20 diverging in a downstream direction and in a clusteras shown, as is more particularly described in U. S. Pat. No. 3,308,344to Harold Smith and George A. Korkos, A lead 21 connects the source withthe needles via a mounting rod or needle 22 which may be carried bystreamlined insulator body 23. Further, an insulative shroud may projectat 24 in protective relation to the tips to prevent direct impingementof exhaust flow on the tips, the shroud defining an outlet at 26 forions to pass at 27 from the tips into the exhaust stream. Body 23, andshroud 24 may consist of insulative (as for example plastic) material.Radial ribs 28 may support the body and shroud in the duct 80. Othertypes of shrouds, supports and ion emitting configurations may beemployed so long as the referred to functions and modes of operation arerealized. Duct may be easily attached at 81 to pipe 12, and the lattercarried at 83 by vehicle structure 84.

In FIG. 2, the engine 10a delivers exhaust to the duct 12 via acatalytic reactor 30 operating to change the molecular content of theflow to less noxious form. For example, CO may be oxidized to C0,, andNO dissociated to form N and O in the reactor. Particulate contentemanating from the reactor is processed as described above and as to bedescribed. The reactor 30 could alternatively be placed downstream ofthe ion generator.

The ion generator again includes multiple tips 31 to which high voltage,of selected polarity, is supplied. For example, over 5,000 volts DCnegative may be employed, considering that the ground surface 17 towhich the charged particles are to be attracted is normally positive. Aninsulative support for the needle cluster 31 as indicated at 33, and ashroud at 34.

Means is provided to pass auxiliary gas to the tips to travel with theions into the exhaust flow 35. Such means may include an air scoop orpump 36 outside the duct 80, and a line 37 to deliver the air to the iongenerator, as for example to porting 38 in the support 33 opening to theregion 39 in the shroud containing the needle cluster. Such air flow 101tends to prevent exhaust backflow into the shroud, keeping the needlesand tips clean and free of exhaust deposits.

In FIG. 3, exhaust from engine 40 is delivered at 41 to a vertical pipeor stack 42 as is found on trucks carrying Diesel engines. Iongenerators 43, shrouded at 50, are carried by the stack wall and withspacing such as to direct positive ions 102 into the upward flow 44 ofexhaust. A charged particle trap, as for example, a negatively chargedgrid or grids 45 is mounted downstream of the generators 43. Thegenerators may produce positive ions to positively charge theparticulate content of the exhaust, voltage supply being indicated at46. Trap 45 may alternatively consist of steel wool or the like, and maybe removable replacement, as facilitated by removal of stock uppersection 42a. An insulative screen or liner 48 extends within the stackbetween the ion generator 43 and the grid or grids.

We claim:

1. Internal combustion engine exhaust fume abatement apparatuscomprising, in combination,

a. an exhaust duct for passing a stream of engine products of combustionhaving electrically chargeable content,

b. means including an ion generator comprising multiple pointed tips toeffect a flow of ions into said stream, with ion density and polarity toso change the electrical charge of said content as to enhance subsequentprecipitation thereof on a surface,

c. an insulative shroud for said tips and exposed to said stream in anupstream direction, the shroud extending in protective relation to thetips to prevent direct impingement thereon of the engine products ofcombustion, and the shroud defining a downstream facing outlet for ionsto pass from the tips to the stream path downstream of the tips, and

d. the duct having an electrically insulative lining extending from aregion upstream of said shroud outlet and at the exterior thereof to aregion proximate an outlet to the atmosphere defined by the duct toinhibit neutralization of said ions during their flow in the duct.

2. The combination of claim 1 including an internal combustion engineoperatively connected with said duct to supply said stream thereto.

3. The combination of claim 1 wherein said means includes a high voltagesupply electrically connected with said tips.

4. The combination of claim 1 wherein said tips are exposed to saidstream in a downstream direction, only.

5. The combination of claim 1 where said shroud tapers in an upstreamdirection and extends in the duct to reduce the duct cross sectionalarea thereby effecting an increase in the stream velocity past theshroud and tips for mixing with the ions 6. The combination of claim 5including means to pass auxiliary gas to said tips to travel with theions into the stream.

7. The combination of claim 1 wherein said ion generator includes asource of positive voltage in excess of +l0,000 volts to effect positiveion flow into the stream.

8. The combination of claim 1 wherein said duct is defined by a vehicletail pipe with said duct outlet directed toward the ground underlyingthe vehicle.

1. Internal combustion engine exhaust fume abatement apparatuscomprising, in combination, a. an exhaust duct for passing a stream ofengine products of combustion having electrically chargeable content, b.means including an ion generator comprising multiple pointed tips toeffect a flow of ions into said stream, with ion density and polarity toso change the electrical charge of said content as to enhance subsequentprecipitation thereof on a surface, c. an insulative shroud for saidtips and exposed to said stream in an upstream direction, the shroudextending in protective relation to the tips to prevent directimpingement thereon of the engine products of combustion, and the shrouddefining a downstream facing outlet for ions to pass from the tips tothe stream path downstream of the tips, and d. the duct having anelectrically insulative lining extending from a region upstream of saidshroud outlet and at the exterior thereof to a region proximate anoutlet to the atmosphere defined by the duct to inhibit neutralizationof said ions during their flow in the duct.
 2. The combination of claim1 including an internal combustion engine operatively connected withsaid duct to supply said stream thereto.
 3. The combination of claim 1wherein said means includes a high voltage supply electrically connectedwith said tips.
 4. The combination of claim 1 wherein said tips areexposed to said stream in a downstream direction, only.
 5. Thecombination of claim 1 where said shroud tapers in an upstream directionand extends in the duct to reduce the duct cross sectional area therebyeffecting an increase in the stream velocity past the shroud and tipsfor mixing with the ions.
 6. The combination of claim 5 including meansto pass auxiliary gas to said tips to travel with the ions into thestream.
 7. The combination of claim 1 wherein said ion generatorincludes a source of positive voltage in excess of +10,000 volts toeffect positive ion flow into the stream.
 8. The combination of claim 1wherein said duct is defined by a vehicle tail pipe with said ductoutlet directed toward the ground underlying the vehicle.